<template>

  <div class="app-container">

    <h2 style="text-align: center;">发布新课程</h2>

    <el-steps :active="1" process-status="wait" align-center style="margin-bottom: 40px;">
      <el-step title="填写课程基本信息"/>
      <el-step title="创建课程大纲"/>
      <el-step title="最终发布"/>
    </el-steps>

    <el-form label-width="120px">

      <el-form-item label="课程封面">

        <el-upload
          :show-file-list="false"
          :on-success="handleAvatarSuccess"
          :before-upload="beforeAvatarUpload"
          :action="BASE_API+'/eduOss/file/upload'"
          class="avatar-uploader">
          <img :src="courseInfo.cover" height="150px">
        </el-upload>

      </el-form-item>
      <el-form-item label="课程标题">
        <el-input v-model="courseInfo.title" placeholder=" 示例：机器学习项目课：从基础到搭建项目视频课程。专业名称注意大小写"/>
      </el-form-item>

      <!-- 所属分类 TODO -->
      <el-form-item label="课程分类">
        <el-select
          v-model="courseInfo.subjectParentId"
          placeholder="一级分类" @change="subjectLevelOneChanged">
          <el-option
            v-for="subject in subjectOneList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"/>
        </el-select>
        <!-- 二级分类 -->
        <el-select v-model="courseInfo.subjectId" placeholder="二级分类">
          <el-option
            v-for="subject in subjectTwoList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"/>
        </el-select>
      </el-form-item>
      <el-form-item label="学院分类">
        <el-select
          v-model="courseInfo.academyId"
          placeholder="请选择">
          <el-option
            v-for="i in academyList"
            :key="i.id"
            :label="i.name"
            :value="i.id"/>
        </el-select>
      </el-form-item>
      <!-- 课程讲师 TODO -->
      <!-- 课程讲师 -->
      <el-form-item label="课程讲师">
        <el-select
          v-model="courseInfo.teacherId"
          placeholder="请选择">
          <el-option
            v-for="teacher in teacherList"
            :key="teacher.id"
            :label="teacher.name"
            :value="teacher.id"/>
        </el-select>
      </el-form-item>

      <el-form-item label="总课时">
        <el-input-number :min="0" v-model="courseInfo.lessonNum" controls-position="right" placeholder="请填写课程的总课时数"/>
      </el-form-item>
      <el-form-item label="课程简介">
        <tinymce :height="300" v-model="courseInfo.description"/>
      </el-form-item>
      <el-form-item label="课程价格">
        <el-input-number :min="0" v-model="courseInfo.price" controls-position="right" placeholder="免费课程请设置为0元"/> 元
      </el-form-item>
      <el-form-item>
        <el-button :disabled="saveBtnDisabled" type="primary" @click="saveOrUpdate">保存并下一步</el-button>
      </el-form-item>
    </el-form>
  </div>
</template>
<script>
import course from '@/api/edu/course'
import subject from '@/api/edu/subject'
import teacher from "@/api/edu/teacher";
import Tinymce from '@/components/Tinymce'
import Academy from "../../../api/edu/Academy";
export default {
  name:'info',
  components:{Tinymce},
  data() {
    return {
      saveBtnDisabled:false,
      courseId:'',
      courseInfo:{
        title: '',
        academyId:'',
        subjectId: '',//二级分类id
        subjectParentId:'',//一级分类id
        teacherId: '',
        lessonNum: 0,
        description: '',
        cover: '/static/01.jpeg',
        price: 0
      },
      BASE_API: process.env.BASE_API, // 接口API地址
      teacherList:[],//封装所有的讲师
      subjectOneList:[],//一级分类
      subjectTwoList:[],//二级分类
      academyList:[],
    }
  },
  created() {
    //初始化所有讲师
    this.getOneSubject()
    this.getListTeacher()
    this.getAcademyList()
    if(this.$route.params&&this.$route.params.id){
      this.courseId=this.$route.params.id
      this.getCourseById()
    }else{
      //初始化一级分类
    }
  },
  methods:{
    getAcademyList(){
      Academy.getAllAcaList().then(res=>{
        this.academyList=res.data.acaList
      })
    },
    //上传封面成功调用的方法
    handleAvatarSuccess(res, file) {
      this.courseInfo.cover = res.data.url
    },
    //上传之前调用的方法
    beforeAvatarUpload(file) {
      const isJPG = file.type === 'image/jpeg'
      const isLt2M = file.size / 1024 / 1024 < 2

      if (!isJPG) {
        this.$message.error('上传头像图片只能是 JPG 格式!')
      }
      if (!isLt2M) {
        this.$message.error('上传头像图片大小不能超过 2MB!')
      }
      return isJPG && isLt2M
    },
    //点击某个一级分类，触发change，显示对应二级分类
    subjectLevelOneChanged(value) {
      //value就是一级分类id值
      //遍历所有的分类，包含一级和二级
      for(var i=0;i<this.subjectOneList.length;i++) {
        //每个一级分类
        var oneSubject = this.subjectOneList[i]
        //判断：所有一级分类id 和 点击一级分类id是否一样
        if(value === oneSubject.id) {
          //从一级分类获取里面所有的二级分类
          this.subjectTwoList = oneSubject.children
          //把二级分类id值清空
          this.courseInfo.subjectId = ''
        }
      }
    },
    getCourseById(){
      course.getCourseInfo(this.courseId).then(res=> {
        this.courseInfo = res.data.CourseInfoForm
        this.getOneSubject()
        for(let i=0;i<this.subjectOneList.length;i++){
          let one=this.subjectOneList[i]
          if(this.courseInfo.subjectParentId==one.id){
            this.subjectTwoList=one.children;
        }
        }
      })

    },
    //查询所有的一级分类
    getOneSubject() {
      subject.getSubjectList().then(response => {
          this.subjectOneList = response.data.items
        })
    },
    //查询所有的讲师
    getListTeacher() {
      teacher.getListTeacher().then(response => {
          this.teacherList = response.data.teachers
        })
    },
    update() {

      course.updateCourseInfo(this.courseInfo,this.courseId).then(res=>{
        this.$message({
          type: 'success',
          message: '修改成功!'
        });
        this.$router.push({path:'/course/chapter/'+this.courseId})
      })
    },
    addCourse(){
      course.saveCourseInfo(this.courseInfo).then(response => {
          //提示
          this.$message({
            type: 'success',
            message: '添加课程信息成功!'
          });
          this.$router.push({path:'/course/chapter/'+response.data.courseId})
      })
        },
    saveOrUpdate() {
      if(!this.courseId){
        this.addCourse()
        }
      else{
        this.update()
        }
    }
  }
}
</script>
<style scoped>
.tinymce-container {
  line-height: 29px;
}
</style>
